The invention relates to a two-for-one twisting or cabling spindle apparatus.
Modern two-for-one twisting or cabling spindle apparatus generally have a stationary protective pot to receive a supply bobbin, a hollow bobbin axle to guide a yarn through the twisting spindle apparatus and a rotatably mounted, driveable spindle arranged below the supply bobbin. In other words, in two-for-one twisting or cabling spindle apparatus of this type, the yarn is drawn off upwardly from a stationary supply bobbin, inserted into the upper end of the hollow bobbin axle and deflected downwardly in the process. Within the bobbin axle, the yarn is guided via a yarn brake and then leaves the region of the bobbin axle via a radial opening, which is arranged in a component of the rotatably mounted, driveable spindle. After leaving the radial opening, the yarn is temporarily stored on a storage disc of the spindle before it is guided to a stationary balloon yarn guide arranged above the protective pot. In the process, the yarn forms a yarn balloon rotating about the protective pot because of the rotation of the spindle between a so-called discharge plate arranged in the region of the storage disc and a balloon yarn guide arranged above the protective pot. After passing the balloon yarn guide, the twisted yarn is wound by a winding mechanism to form a take-up bobbin.
In two-for-one twisting or cabling spindle apparatus of this type, the shape and size of the yarn balloon being formed during the twisting process depend inter alfa on the diameter of the yarn discharge element of the spindle. In other words, the two-for-one twisting or cabling spindle apparatus often have, as described, for example in German Patent Publication DE 10 2006 029 055 A1, a spindle driven by means of a tangential belt, which in turn has a revolving storage disc and a yarn discharge plate fixed to the storage disc and arranged above the storage disc.
In order to prevent the yarn balloon coming into contact with the stationary protective pot during the twisting process in the case of friction-sensitive yarn materials, such as, for example, polypropylene, polyester or polyacrylics, which risks a yarn break, the diameter of this known yarn discharge plate is dimensioned such that it is above the diameter of the stationary protective pot. This means that the yarn balloon circulating between the yarn discharge plate and the balloon yarn guide arranged above the protective pot generally has a relatively large diameter.
However, as it is known that large yarn balloons lead to relatively large ventilation losses and therefore to an increased energy requirement of the two-for-one twisting spindle, various tests have already been carried out in the past, in particular in connection with less friction-sensitive yarn materials, such as, for example, cotton, to reduce or limit the diameter of the yarn balloons.
Two-for-one twisting spindle apparatus are described, for example, in German Patent Publication DE 44 04 555 C1 which, in addition to a stationary protective pot receiving the supply bobbin have a cylinder-like balloon limiter comprising the protective pot.
In two-for-one twisting spindle apparatus of this type, the production of a yarn balloon which is relatively large in diameter is effectively prevented in that the yarn immediately runs onto the inside of the balloon limiter after leaving the yarn discharge plate, which is relatively large in diameter, of the spindle.
The drawback in these known two-for-one twisting spindle apparatus is, however, the relatively long physical contact of the revolving yarn balloon with the stationary balloon limiter. As the stresses acting on the yarn owing to such stationary balloon limiters are relatively high, two-for-one twisting spindle apparatus of this type can only be used for relatively insensitive yarns.
Comparable two-for-one twisting spindle apparatus with stationary balloon limiters are also known from German Patent Publications DE-OS 1 813 801 or DE 33 47 318 A1.
In the two-for-one twisting spindle apparatus according to German Patent Publication DE-OS 1 813 801, the supply bobbin is, however, not arranged for protection in a stationary protective pot, but stands open on a component of the two-for-one twisting spindle apparatus configured as a bobbin carrier. In order to avoid contacts between the revolving yarn balloon supported outwardly on a cylindrical balloon limiter and the supply bobbin, a cylinder-like yarn guide arranged between the balloon limiter and the supply bobbin is also provided in these two-for-one twisting spindle apparatus and surrounds the supply bobbin at the level of the balloon limiter upper edge.
The two-for-one twisting spindle apparatus according to German Patent Publication DE 33 47 318 A1 has a bulky cylindrical balloon limiter, in which a stationary protective pot, which has conical end regions, is mounted.
Thus, also in the two-for-one twisting spindle apparatus known from German Patent Publication DE-OS 1 813 801 or DE 33 47 318 A1, the maximum diameter of the developing yarn balloon is predetermined by the internal diameter of a stationary, outer balloon limiter, so the yarns to be processed are not insignificantly loaded during the twisting process.
Furthermore, a two-for-one twisting spindle apparatus is described in German Patent Publication DE 19 31 291 C2, in which the stationary protective pot, which has a supply container for a lubricant in the base region, is slightly convexly rounded. The protective pot is also equipped, in the region of the supply container, with an annular disc, which consists of an absorbent material. In this known two-for-one twisting spindle apparatus, the yarn, after leaving the yarn discharge plate, which is relatively large in diameter, of the spindle, slides over the annular disc on the protective pot and in the process is wetted with a lubrication or a lubricating means.